Polyethylene-2,6-naphthalene dicarboxylate

DECOMPOSITION OF POLYETHYLENE 2,6-NAPHTHALENE DICARBOXYLATE TO CONSTITUENT MONOMERS USING SUPERCRITICAL METHANOL... 

The manufacture of polyethylene naphthalate) (PEN) is carried out using dimethyl 2,6-naphthalene dicarboxylate (NDC) and EG and is similar to the manufacture of PET from DMT. The IV after the melt is typically in the range of 0.5... 

PB PBI PBMA PBO PBT(H) PBTP PC PCHMA PCTFE PDAP PDMS PE PEHD PELD PEMD PEC PEEK PEG PEI PEK PEN PEO PES PET PF PI PIB PMA PMMA PMI PMP POB POM PP PPE PPP PPPE PPQ PPS PPSU PS PSU PTFE PTMT PU PUR Poly(n.butylene) Poly(benzimidazole) Poly(n.butyl methacrylate) Poly(benzoxazole) Poly(benzthiazole) Poly(butylene glycol terephthalate) Polycarbonate Poly(cyclohexyl methacrylate) Poly(chloro-trifluoro ethylene) Poly(diallyl phthalate) Poly(dimethyl siloxane) Polyethylene High density polyethylene Low density polyethylene Medium density polyethylene Chlorinated polyethylene Poly-ether-ether ketone poly(ethylene glycol) Poly-ether-imide Poly-ether ketone Poly(ethylene-2,6-naphthalene dicarboxylate) Poly(ethylene oxide) Poly-ether sulfone Poly(ethylene terephthalate) Phenol formaldehyde resin Polyimide Polyisobutylene Poly(methyl acrylate) Poly(methyl methacrylate) Poly(methacryl imide) Poly(methylpentene) Poly(hydroxy-benzoate) Polyoxymethylene = polyacetal = polyformaldehyde Polypropylene Poly (2,6-dimethyl-l,4-phenylene ether) = Poly(phenylene oxide) Polyp araphenylene Poly(2,6-diphenyl-l,4-phenylene ether) Poly(phenyl quinoxaline) Polyphenylene sulfide, polysulfide Polyphenylene sulfone Polystyrene Polysulfone Poly(tetrafluoroethylene) Poly(tetramethylene terephthalate) Polyurethane Polyurethane rubber... 

Polyethylene naphthalate (PEN) polyesters are made from 2,6-naphthalene dicarboxylic acid or 2,6-naphthalene dicarboxylic acid, dimethyl ester. They have higher temperature resistance than amorphous PET and are increasingly used in applications requiring heat sterilisation of the food/drink, although PEN at the moment is significantly more expensive. Table 10.5 lists commonly used substances in polyesters. 

The kinetics of crystallization of polyethylene-naphthalene-2,6-dicarboxylate (PEN) and of copolyesters of this material with p-hydroxybenzoic acid (PHB) was studied by Wiswe, Gehrke, and Zachmann. PEN crystallizes in two different crystal modifications. One modification is obtained by crystallization at comparatively low temperatures, the other one is obtained sometimes when the material is crystallized near the melting point. Fig. 55 shows the change in the wide angle scattering during isothermal crystallization at 167 °C and 245 °C. 

PEN Poly(ethylene 2,6-naphthalene dicarboxylate), or polyethylene naphthalate... 

Tg measurements have been performed on many other polymers and copolymers including phenol bark resins [71], PS [72-74], p-nitrobenzene substituted polymethacrylates [75], PC [76], polyimines [77], polyurethanes (PU) [78], Novolac resins [71], polyisoprene, polybutadiene, polychloroprene, nitrile rubber, ethylene-propylene-diene terpolymer and butyl rubber [79], bisphenol-A epoxy diacrylate-trimethylolpropane triacrylate [80], mono and dipolyphosphazenes [81], polyethylene glycol-polylactic acid entrapment polymers [82], polyether nitrile copolymers [83], polyacrylate-polyoxyethylene grafts [84], Novolak type thermosets [71], polyester carbonates [85], polyethylene naphthalene, 2,6, dicarboxylate [86], PET-polyethylene 2,6-naphthalone carboxylate blends [87], a-phenyl substituted aromatic-aliphatic polyamides [88], sodium acrylate-methyl methacrylate multiblock copolymers [89], telechelic sulfonate polyester ionomers [90], aromatic polyamides [91], polyimides [91], 4,4"-bis(4-oxyphenoxy)benzophenone diglycidyl ether - 3,4 epoxycyclohexyl methyl 3,4 epoxy cyclohexane carboxylate blends [92], PET [93], polyhydroxybutyrate [94], polyetherimides [95], macrocyclic aromatic disulfide oligomers [96], acrylics [97], PU urea elastomers [97], glass reinforced epoxy resin composites [98], PVOH [99], polymethyl methacrylate-N-phenyl maleimide, styrene copolymers [100], chiral... 

Colombini and co-workers [42] used DMTA and DETA (Chapter 12) to explore the relaxation processes occurring in amorphous and semi-crystalline polyethylene naphthalene-2,6,-dicarboxylate. The two secondary relaxations P and P, the main a-relaxation and the p-relaxation processes were revealed by both mechanical and electro viscoelastic responses of the polymer. The DMTA results clearly identified the T(a) loss factor peak. 

Polyethylene 2,6-naphthalene dicarboxylate No degradation by soil micro-organisms after 50 d. [111]... 

Polyesters are widely used as fibers, although the market share of fibers fell from more than 70% before 1995 to about 60% by 2000, as demand for polyester (PET) bohles increased. To cope with the increased demand for bottles since 1995 more isophthalic acid is being used as a copolymer with ethylene glycol. At the same time, naphthalene dicarboxylate (NDC) has been used to produce a new polyester known as polyethylene terenaphthalate (PEN). The new polyester bohles, although originally very expensive, have lowered gas permeability and are stronger and more heat resistant. Nevertheless, as prices fall, the demand for all types of polyester will continue to rise. 

Hoffman and coworkers found, using the procedures outlined above, reasonably good agreement between the calculated value of Coo and those for polyethylene, isotactic poly-(styrene), poly(l-lacfic acid), isotactic poly(propylene), and poly( -caprolactone).(235) On the other hand the agreementis poor for poly(pivalolactone) (237) as well as for poly(ethylene terephthalate), poly(aryl ether ether ketone) and poly(ethylene naphthalene dicarboxylate). (198) The comparison between theory and experiment, despite the many assumptions made, remains inconclusive. 

Regioselective dialkylation of naphthalene is another reaction of considerable interest as 2,6-dialkylnaphthalenes can be oxidised to naphthalene-2,6-dicarboxylic acid, which is used in the synthesis of the commercially valuable polymer, poly(ethylene naphthalenedicarboxylate) (PEN).22 PEN has properties that are generally superior to those of polyethylene terephthalate) (PET) and has become the polymer of choice for a variety of applications such as in films, industrial fibres, packaging, liquid crystalline polymers, coatings, inks and adhesives. However, the high cost of naphthalenedicarboxylic acid has been a major hindrance to widespread application. 

Figure 1.2. Typical microhardness values of polymers compared with data for metals. LDPE, low-density polyethylene HDPE, high-density polyethylene PA, polyamides POM, polyoxymethylene CEPE, chain-extended polyethylene CF-composite, carbon-fibre composite PS, polystyrene PEN, poly(ethylene naphthalene-2,6-dicarboxylate. (From Balta Calleja Fakirov, 1997.)...

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